It was a deliberate change to teaching and testing methods. I'm old enough to remember the big shift in the UK from "high stakes" 'O' Level examinations to course based GCSE's. One of the reason's cited for the change was to help girls (who were well behind boys in academic achievement at the time), with a system geared towards female learning strategies.

In the book Datatclysm, the author shows pretty conclusively that, while men are excellent at judging physical attractiveness in women, women are terrible at judging it in men. They rate nearly 70% of men as "below average" in physical appearance.

This is pretty clearly a biological adaptation. Women bear almost the sole biological cost of reproduction and infant care (men can't lactate). As a result a cautious strategy, accepting a higher rate of false negatives (thinking a guy has worse genes than he does); is preferable to absorbing the costs of a false positive (thinking a guy has better genes than he does).